Immuno-histological observations upon the development of reticulum cell sarcoma in the mouse.

Detailed observations were made of the development of "reticulum cell sarcoma" in four strains of laboratory mice: SJL/J, NZB, PBA and (BALB/C X A)F1 hybrids injected with parental (BALB/C) spleen cells. Morphological evidence of a florid B cell immune response was present in all four strains, and was succeeded by a phase of atypical lymphoid hyperplasia, prior to the appearance of malignant neoplasms in lymph-nodes or spleen. These neoplasms correspond to descriptions of "reticulum cell sarcoma" of the mouse. The demonstration, by immunoperoxidase methods, of immunoglobulin within a proportion of these "malignant reticulum cells" reinforces the opinion, based on the morphological evidence of hyperplasia progressing to neoplasia, that the "reticulum cell sarcoma" of the mouse is B lymphocyte derived.